Polyolefins such as high density polyethylene (HDPE) homopolymer and linear low density polyethylene (LLDPE) copolymer can be produced using various combinations of catalyst systems and polymerization processes. In some end-use applications, it can be beneficial for the catalyst system employed to facilitate efficient incorporation of a comonomer during polymerization to produce lower density copolymers. In other end-use applications, it can be beneficial to produce high melt flow copolymers having lower densities. Accordingly, it is to these ends that the present invention is directed.